Christian Mainka is a Security Researcher at the Ruhr University Bochum, Chair for Network and Data Security. Since 2009, he focuses on XML and Web Services technologies and develops his penetration testing tool WS-Attacker and has published several papers in the field of XML security related topics on scientific workshops and conferences. Nowadays, he used to break Single Sign-On protocols and implementations. Additionally to his scientific carrier he is a cofounder of Hackmanit GmbH and provides expert audits, security trainings, and penetration tests in the area of Message-Level Security.